Thread puller for automatic stop sewing machines



Jan. 19 1929. 1,569,992

M. MG'CANN THREAD PULLER FOR AUTOMATIC STOP SEWING MACHINES Filed May 16. 1925 3 Sheets-Sheet 1 Jan. 19 1926. M. M cANN THREAD FULLER FOR AUTOMATIC STOP sawme mcamns s She ets-Sheet 2 Filed May 16, 1925 Jan. 19,1926. 1,569,992 M. MCCANN 'rnwm mama FOR AUTOMATIC STOP sswme MACHINES Filed May 16. 1925 s Sheets-Shet :5

Patented .1... 19, 1926.

UNITED STATES 1,569,992 PATENT OEFl CE.

MIGKAEL-MGCANN, OF GLENMORRIS, KEW YORK, ASSIGNOR TO FREDERICK OSANN comrm, or new Yonx, N. Y.,

A CORPORATION OF NEW YORK.

THREAD FULLER FOR AUTOMATIC STOP SEWING MACHINES.

Application filed lay 16, 1925. Serial No. 30,752.

' To all whom it may concern:

Be it known that 1, MICHAEL MCCAHH, a citizen of the United States of America, residing in Glenmorris, L. 1., in the county I of Queens and State of New York, have invented certain new' and useful Improvements in'Thread Pullersfor Automatic Stop Sewing Machines, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

My invention relates to sewing machines having automatic stop mechanism such as,

for instance, the machine of my former.

.25 stantially parallel to the needles and with means actuated in timed relation to the stopping and starting of the machine whereby the tension device is, immediately before the stopping-of the machine, moved upward so go as to engage the threads at more elevated points, and whereby also the tension device is moved downward as the machine is started so that there is a free length of thread above the needles which is carried down by the needles without frictional resistance.

Generally speaking, my invention consists in mechanism for effecting this object which in its preferred detail will be best under* stood as described in connection with the drawings which illustrate my improved 'mechanism as ap lied to the machine of my former patent an in which Figure 1 is a side elevation of the head of the machine with 'my improved device applied toit. V

- 'Figure 2 is a plan view of mechanism shown in Fig. 1. V Q

Figure 3 is a front elevation of the head showing my tension device indts normal lower position.

" Figure 4 is a similar view showing the tension device in elevatedposition.

Figure 5 -1s a plan view showing on a larger scale the tension device and the means cates.

for actuatin it by the movements of the pull off rod Figure 6 is a sectional plan view similar in the parts shown to Fig. 3 of my former Patent 1,483,185, and illustrating the stop motion and the correlated mechanism for actuating the pull off rod Q and,

Figure 7 is a-sectional elevation on line 7-7 of Fig. 6.

A indicates the casing enclosing the lower portion of the machine; A the upwardly extending portion of the casing.- A the horizontal portion and A the head proper.

C, see Figures 6 and 7, is a downwardlly extending rib in the casing portion A.

is the main driving shaft. D, is a hub extension of casing A to rovide a sufiicient bearing for shaft D. D is a disk having the eneral construction described in my former atent 1,483,185. D and D are fast and loose pulleys on the shaft D. D, an eccentric secured to this shaft. D and D cams secured to the shaft D as in my said formerpatent. E, a rock shaft actuated as described in my former patent, from the cocentric D" and actuating, through the lever E the needle bar E, to the lower end of which are secured the needles-indicated at E. G is a rock shaft actuated as described 'in my former Patents 1,483,185 and 1,461,-

428, and by means of which an oscillating, reci rocat'ing moveinent is given to the D through gears,-o ne of which is indicated at F and having attached to it a cam F which engages the forked end F of the pivoted block fully shown and described in e Gr in which the needle bar E reci ro- F is a shaft driven from the s aft:

my said formeratents. I is a shaft which, f. as shown in my ormer Patent 1,483,185, has

secured toit the cams I and I, the first cam interacting with the lever ends F and the second interactin' with the lever K and rod K, all as descri ed in my former patent. p M is the sto shaft of the machine having buffers M an M secured to it which limit its longitudinal sliding motionr -M' is a forked lever arm secured to the shaft M andcarrying the stop "finger M. Mis a belt shifting arm, m being the belt and M a spring actinsi to press the shaft Mtoward .1

the right, as

own in Fig. 6. "N- is an arm pivoted on ,the shaft M and carrying a-pin cated at indicated at N and having an extension N which is engaged, as described in my former patent, by the ends P of the lever P. O is a pivot secured to the frame of the machine on which is pivotally secured the hook O normall pressed into osition to engage the pin N y the spring 8. M is a spring normally tending to move the shaft M toward the right and at M I have indicated a usual crank lever by which the shaft M is shifted toward the left in starting the machine. Q is an arm also pivoted on the shaft M having a portion Q which engages with cams D and D, as described in my former patent, this arm also having a laterally extending arm Q which extends beneath the lower end of the pull off rod, indicated at Q. The arm Q is normally drawn downward by the spring indicated at Q, Fig. 7, and rests on the adjustable screw, indicated at Q. The pull off rod at Q, as shown in Fig. 1, has a thread engaging device Q at its top and is normally pressed downward by a spring indicate at Q. The threads indig pass through the tension device indicated at S, under hooks indicated at g and then through proper guides through a take u device indicated at S which moves with the small bar E.

, In all of the above described parts the machine illustrated is the same as the machine of my former Patent 1,483,185, and the operation of the machine is the same, the arm N, at the completion of the sewing of a buttonhole, being pressed downward so as to disengage the hook O whereupon the shaft M moves toward the right until the edge of the portion Q of the arm Q comes in contact with the side of the cam D Then, as the cam revolves until its lower portion releases the portion Q of the arm Q, the shaft M is enabled to complete its right hand movement so that the stop finger M engages the recesses provided in the disk D and stops the machine. Immediately before the machine is brought to a stop the cam D lifts the arm Q and through its laterally extenduflg arm Q lifts the pull off rod Q,'-pulling o the desired amount of thread between the thread engaging device and the books 9 9'- new 1n my present machine, 3 isa rock shaft which I secure in proper bearings and which on its outer end has secured to it an arm 4 carrying on its free end a tension device indicated at 5, through which the threads-pass immediately above the needles. Also secured to the shaft 3 is a lever arm 6, having a slot indicated at 7 in its free end which is engaged by a pin 9, attached to arm 8, which is secured in turn to the pull off rod Q.

In operation, the normal position of the lever itself and the tension device carried b it, is that shown in Fig. 3. When, through the described mechanism, the pull off rod Q is raised, the rock shaft 3 isactuated and the arm 4 and tension device 5, rises to the position shown in Fig. 4, the thread sliding.

through the tension device as it is moved upward. Immediately after the shifting of the position of the tension device, the machine comes to a stop. The machine is started again by shifting the stop shaft M toward the left and as this moves the arm Q so that it is no longer supported on the cam D this arm at once moves downward, as does also the supported pull off rod Q, with the result that, as, or immediately before, the needles begin to operate, the tension device 5 moves back to the position shown in Fig. 3, so that the needles can movedownward to begin the sewing of another button-hole without exerting any pull on the threads It will be clear that a supply of thread for the downward movement of the tension device is supplied by the downward movement of the takeup element S (which is fastened to and moves with the needle bar) from its position as shown in Fig. 4 to that shown in Fig. 3.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a sewing machine having an automatic stop device for arresting the motion of the machine, the combination therewith of a tension device through which the threads pass located close to the needles and movable through a path substantially parallel to the needles, a machine element, means for holding and retracting said element in and to normal retracted position, means connecting the said machine element with the tension device to move it u ward when the machine element is moved rom normal position and downward when said element returns to normal position, and means moving in coordinated relation to the stop motion actuating mechanism whereby the said machine element is shifted from normal position immediately before the machine is stopped and permitted to return to normal position substantially simultaneously with the starting of the machine.

'2: In a sewing machine having an auto- Referring now to the features which aae matic stop device for arresting the motion of'the machine, the combination therewith of a tension device through which the threads pass located close to the needles and movable through a path substantially parallel to the needles, a pull off device, means for holding and retracting said pull off device in and to normal retracted sition, means connecting the said pull of? device with the tension device to move it upward when the pull oif device is moved from normalfosition and downward when said pull off evice returns to normal ition, and means moving in coordina relation to threads i pass located close to the needles and movable throu h a path substantialliy parallel to the nee es, a verticall exten mg rod carrying a pull ofi device at its 15 upper end, means operating in timed relation to the stop motion for elevating therod 'ust beforethe machine stops and returning it to normal retractedposition as the machine'is started, ashaft, means 0 ratively connecting said shaft to the pul ofi rod and means for actuating the movable tension device operated by said shaft.

' MICHAEL MoCANN. 

